Hot Corrosion of Slag Line in Plaster of Tundish in Continuous Casting of Steel

Plasters are produced from a light refractory material, mainly MgO (M.P. ۲۸۰۰ºC), a binder, and a void forming substance for insulating purposes. Different oxides from the slag penetrate into these voids and provide low melting-point phases suchasrhodonite (MnSiO۳) (۱۲۹۰ºC), tephorite (Mn۲SiO۴) (۱۳۴۵ºC), merwinite (Ca۳MgSi۲O۸) (۱۵۷۵ºC), monticellite (CaMgSiO۴) (۱۴۹۰ºC), and enstatite (MgSiO۳) (۱۵۶۰ºC). XRF, XRD, and microanalysis by EDX were used to investigate and evaluate the penetration of different oxides to distances below the slag-plaster interface. Results show that SiO۲ and MnO are the most deteriorating while alumina and calcite are the least harmful. It is suggested that rice husk cover on melt, which is rich in SiO۲, be replaced with insulating powders rich in Al۲O۳ and CaO, and that slag basicity be increased in order to decrease the slag line hot corrosion of plaster

کلیدواژه ها:

Corrosion ، Slag ، Plaster of tundish ، Slag line